Most people do not stop to think about how well their mobile phones or the location apps they use on them reveal their locations or movement. They just want their phones and apps to work. Professor Derek McAuley explains how phone companies pinpoint your location and handle the high volume of phone traffic in today’s video.

Ardit_Dashaj
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2014-06-06T17:23:14Z —
#2

Hey, it's so easy to play with fallacies on-line, and what you're saying is just partly true. I dare to say that in your statements is missing the real reason of why the Location Process is done and is necessary, and partly you are saying about the risks if this process is theoretically misused!

It does not have something to do with spying people but serving DATA process (commutation) fast and well and this is the same process that happens inside of a LAN Switch/router but in a large scale, for without it, a phone call may need more than a week to find the location of the other phone whom calling.

You said on video, when you receive your voice like echo of itself, it means that someone is listening your conversation.

This is a process that has to do with RX diversity, reflected signal, BER, etc. This happens if Network is analyzing communication quality and switching to HandOver Process. If you have a possibility to record those data streamed (impossible but IF), it is impossible for a normal person to decode them, because to do that many real devices equal to a BSC is needed to do this process, but still needs a lot of conditions to fulfill. From GSM Network to another one, algorithms are not the same, even if you use OpenBSC!!!

What is happening in real when an MS (mobile station) is powered on? It communicates with MTX (mobile transmission processor else knows as mobile network core) every minute (even if you're not using your phone at all), by sending to the center many service data streaming also known as ServiceCHannels over a carrier signal on which all these ServiceCHannels are encoded as one single signal!

What encoded data are partially decoded on BSC or MTX??? Some of them are: MS Location (full DIP), RX Level -dBm, PowerReflected level, BER etc. VoiceCHannels are not decoded into analog signal inside of MTX except for those needed by Security Agencies (with special ordinance), instead they usually are just routed to the physical channel at the physical location of BS (Base Station – the station that diffuse GSM signal for a local area) where the other phone we're calling is located. This exact and fast location process is done by VLR and HLR workstations (that are explained some paragraphs down).

Usually on one UpLINK - DownLINK channels on GSM 2 (that you are mostly referring) just for voice channel includes three processes: Sampling, Quantization & Encoding (this last one converts our voice from analog to digital so it can be sent through digital networks, and when we hear a voice on mobile all these processes are reversed back) and these three processes are done at speed of 8000 cycles per second and the voice CHannel and all other CHannels are encoded once again to an single Carrier signal to reduce physical communication channels number into one UpLink and one DownLink and reduce the bandwidth. Depending on the networks, more Communication channels on GSM 2.5 were added as many new services were added for users but all encoded into one carrier signal.

How does this encoded signal can be decoded normally without fulfilling some technical conditions? In theory this can be done, but what about practice??? Some people believe that using a phone as a receiver connected to a computer they can decode VoiceCHannels. This brings us back to another problem. How is that phone accessing the same VoiceCHannels assigned to another phone communication? Some say by cloning SIM card. Sorry but a Good configured GSM Network (mostly they are better than that) if detects two IMSI equal, interrupt the communication of those mobiles and if the problem persist, makes your SIM unavailable to connect to the network, and a user has to go to take another SIM with the same number but different code inside!

We both said "MS Location" what is this? Each subscriber of GSM even if he is subscriber of another network using Roaming Services, on the network from where he gets the signal, based on network topology, his MS transmits its location (and full DIP). that is recorded in two workstation Machines (computers), HLR (home location record) & VLR (visitor location record). Are these two workstation computers for spying our location? Not really, they are there for a technical reason, but from here can be accessed your real location and the whole trace of it. Before, I did say about VoiceCHannels routed to exact physical channel at exact BaseStation where the other phone being called is really located. Then, this process done in one second because VLR or HLR have the exact location of it, the same as of yours. So, without these two workstation machines, one phone call would needed more than a week to do that! These two machines are just for technical reasons!

These two machines are locked and just an operator on Control Room can access them (just locally) and no one (even police and security agencies) can access them by an external network! Saying that this really happens, means that you don't have any idea how these mechanisms works. At this point, naturally we ask: "Then how Security Agencies or Special Police team got spying us at the time of GSM 2G and GSM 2.5G and still doing it? Simply, they have an agreement from government that forces GSM companies to handle your data to them (location, SMS, phone calls list and info and to decode in real time UpLINK & DownLINK if a higher importance situation rise up) but for each time a special court verdict is needed, otherwise these data are illegal, can not be presented in court against a user and the operator and the company that facilitated access to those can be sued for that. Do you know any company that is ready to pay millions of dollars just because of spying a user, or closing down their business for that???

Are then made any illegal peeps from different agencies and how were they done at the time of GSM 2G & 2.5G? Simply they used (in many cases) SMS that contained pieces of EEPROM code or command that forced your mobile (automatically to execute) to forward your voice and SMS through different services to their receivers machines or terminals by using different communication possibilities your phone had, such as blue-tooth, SMS, 1TimeCallForward etc. About this last one, users may remember in old days, how many times they were sure to have digit the right number, but an wrong person on an wrong (unknown) number, answered that call, and kind of gently asked who you are and whom you are calling too, and trying to keep you as long as they could in that conversation!

Now technology has changed, GSM evolved to UMTS, phones has the capability of a mini computer. Are they more secured? NO! With today's evolution of technology, simply it's more easy to retrieve your informations without involving GSM companies, because it is the user itself thathandles its data. Each browser has GeoLocation services active included on it, and even if you hide your IP behind proxies, you are telling exact location to every one that needs to know it, your data can be forwarded in about 4 seconds on the other side of earth, and this is what PRISM uses. A user can protect himself only by throwing way his devices and starts living on the forests like in prehistoric ages, otherwise there is no escape from being traced!

Now, insinuations that GSM companies spy users locations, making them believe that each company spy them or did (expressed in your contest) is playing the interesting man. Have you ever worked for any companies you're talking or just explaining an seminar lesson for the students?

You may ask... how do I know? Well, guess where I did work in the past and what is my profession too.

system
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2014-06-15T17:40:30Z —
#3

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